KPV Guide: Evidence & Sourcing

KPV at a glance

What it is

KPV (Lys-Pro-Val), a synthetic tripeptide identical to residues 11-13 of alpha-melanocyte-stimulating hormone. C16H30N4O4, average molecular weight 342.43 Da, CAS 67727-97-3, PubChem CID 125672. Also listed as alpha-MSH(11-13) and ACTH-(11-13).

Where it comes from

It is the C-terminal fragment of alpha-MSH, whose full 13-residue sequence is SYSMEHFRWGKPV. The last three letters of that sequence are the compound.

Researched for

Anti-inflammatory signalling, principally in intestinal models. The published work concentrates on colitis, colitis-associated tumorigenesis, keratinocyte signalling and antimicrobial activity against S. aureus and C. albicans.

Established mechanism

Uptake through PepT1, the di/tripeptide transporter, followed by inhibition of NF-kappaB and MAP-kinase signalling. Dalmasso 2008 showed the effect disappears when PepT1 is absent, which is unusually direct mechanistic evidence for a compound in this category.

The route question

The two foundational colitis papers administered KPV orally, and the subsequent delivery literature is about getting it to the colon by mouth. The dominant research-market format is a lyophilised vial for subcutaneous use. The evidence base and the product format point in different directions, which is worth understanding before reading any dosage figure.

Human evidence

None. A PubMed search returns no clinical trial of KPV, and ClinicalTrials.gov lists no registered interventional study of the compound. Every efficacy result below is from cells, mice or both.

Half-life

No published human pharmacokinetic study reports one. The figures circulating on commercial pages are not traceable to a measurement. See the half-life section for what can honestly be said instead.

Regulatory status

Not approved by FDA for any indication, and not an approved drug in any major regulated market. Sold and discussed for research and educational use only. Not a controlled substance; verify current status independently before assuming anything about a specific context.

Educational reference. This page does not publish dose ranges or reconstitution arithmetic.

What it is / mechanism

KPV is about as small as a signalling peptide gets: three residues - lysine, proline, valine - with an average molecular weight of 342.43 Da (C16H30N4O4, CAS 67727-97-3). Its origin is what makes it interesting. Alpha-melanocyte-stimulating hormone is a 13-amino-acid hormone with the sequence SYSMEHFRWGKPV, and KPV is simply the last three letters of it. The same tripeptide is also the 11-13 fragment of ACTH, which is why chemical suppliers list it under both names. Alpha-MSH has been known since the 1980s to have anti-inflammatory activity alongside its much better-known pigmentation activity, and the research question that produced KPV was straightforward: how much of the parent hormone do you actually need to keep the anti-inflammatory part? The answer that emerged is that the C-terminal tripeptide is, in the phrasing of the keratinocyte literature, the smallest minimal sequence reported to prevent inflammation. The reason this matters practically is that alpha-MSH's pigmentation effects run through the melanocortin-1 receptor, and KPV's anti-inflammatory effects largely do not. The cleanest demonstration is in Kannengiesser 2008, which ran DSS colitis in mice carrying a non-functional melanocortin-1 receptor (the MC1Re/e strain). If KPV worked through MC1R, it should have done nothing in those animals. Instead it rescued every animal in the treatment group from death during the colitis protocol. The authors concluded the effects are at least partially independent of MC1R signalling. This is the evidential basis for the claim, repeated everywhere in commercial copy, that KPV gives you alpha-MSH's anti-inflammatory activity without its tanning activity - and it is worth knowing that the claim rests on a specific knockout experiment rather than on inference, because most of the pages making it do not say where it comes from. The mechanism proper was established by Dalmasso and colleagues in Gastroenterology in 2008, and it is unusually well pinned down for a compound of this kind. PepT1 is a di- and tripeptide transporter that is normally expressed in the small intestine and is essentially absent from the healthy colon - but it is induced in the colon during inflammatory bowel disease. KPV, being a tripeptide, is a PepT1 substrate. The group demonstrated this directly with radiolabelled [3H]KPV uptake kinetics and with competition experiments using cold KPV against a known PepT1 substrate. Once inside the cell, nanomolar concentrations of KPV inhibited activation of NF-kappaB and of MAP-kinase inflammatory signalling, and reduced secretion of pro-inflammatory cytokines. The work was done in human intestinal epithelial lines (Caco2-BBE, HT29-Cl.19A) and in human T cells (Jurkat), so both the epithelial and the immune arm were covered. What makes the PepT1 finding more than a mechanistic footnote is its self-targeting logic. The transporter that carries KPV into the cell is the one that inflammation itself switches on in the colon. In principle the peptide concentrates where the transporter is expressed, and the transporter is expressed where the tissue is inflamed. Viennois 2016 tested that logic the hard way, in a colitis-associated cancer model: KPV prevented carcinogenesis in wild-type mice, and when the same treatment was given to PepT1-knockout mice it produced none of the effects seen in wild-types. A compound that does nothing when its transporter is deleted is a compound whose mechanism has been demonstrated rather than proposed, and that is a genuinely stronger position than most peptides in this market can claim. Two further mechanistic strands sit outside the gut. In human keratinocytes, Elliott 2004 found that neither alpha-MSH nor KPV raised cyclic AMP - the second messenger everyone expected, given that alpha-MSH's classical receptor signalling is cAMP-dependent - and instead observed rapid intracellular calcium responses to KPV across a very wide concentration range. That result is one reason the skin-facing literature on this compound is less settled than the gut-facing literature: the signalling pathway in keratinocytes is not the one the receptor pharmacology would predict. Separately, Cutuli 2000 reported direct antimicrobial activity: alpha-MSH peptides including KPV inhibited Staphylococcus aureus colony formation and reduced viability and germ-tube formation in Candida albicans, at concentrations spanning down into the picomolar range, and notably did not blunt neutrophil killing of those organisms the way conventional anti-inflammatory drugs do. The honest summary of the mechanism is therefore split. The intestinal pathway - PepT1 uptake, NF-kappaB and MAP-kinase inhibition, demonstrated by knockout - is well characterised. The dermatological and antimicrobial strands are real published findings but thinner, and the keratinocyte signalling in particular does not yet have an agreed pathway. None of this mechanistic work establishes that KPV does anything useful in a human being, because the step from mechanism to clinical effect has not been taken for this compound.

Researched effects

The effects reported for KPV cluster tightly around inflammation, and the strongest cluster is intestinal. In Kannengiesser 2008, KPV was tested in two independent murine models of inflammatory bowel disease - DSS colitis and CD45RBhi transfer colitis. In the DSS model, treated animals recovered earlier and regained significantly more body weight, inflammatory infiltrates in the colon were significantly reduced on histology, and myeloperoxidase activity in colonic tissue - a standard neutrophil-burden readout - fell significantly. The transfer-colitis arm reproduced the pattern: recovery, weight regain, reduced inflammatory change on histology. Dalmasso 2008 independently found that oral KPV reduced the incidence of both DSS- and TNBS-induced colitis, measured as reduced pro-inflammatory cytokine expression. Two groups, two labs, four models, consistent direction. The colitis-associated cancer result is more nuanced than the headline suggests, and it is worth stating carefully because "KPV peptide cancer" is a common search. Viennois 2016 was primarily a study of PepT1, not of KPV. It found that PepT1 expression is increased in colonic biopsies from patients with colorectal cancer, that overexpressing human PepT1 in mouse intestinal epithelium increased tumour size and burden in an AOM/DSS carcinogenesis model, and that deleting PepT1 decreased tumour number and size. Against that background, KPV - a PepT1 substrate - prevented carcinogenesis in wild-type mice, and did nothing in PepT1-knockouts. So the finding is that a PepT1-transported anti-inflammatory peptide reduced inflammation-driven tumour formation in mice. It is not a finding that KPV treats cancer, and the same paper's data on PepT1 in human tumours cuts in a more complicated direction than a simple benefit claim would allow. Skin and wound-healing interest is real but rests on thinner ground. The keratinocyte signalling work established that KPV produces measurable responses in human skin cells across a very wide concentration range, and KPV appears in review literature on tripeptides in wound healing and skin regeneration. What does not exist is a controlled study showing that applying or injecting KPV improves a skin condition in people. The eczema and psoriasis framing that appears throughout commercial pages is an extrapolation from anti-inflammatory mechanism plus the parent hormone's known dermatological biology, not a reported result. The antimicrobial strand is the least discussed and arguably the most distinctive. Cutuli 2000 showed inhibition of S. aureus colony formation and reduced Candida albicans viability and germ-tube formation, with the effect at least partly mediated by increased cellular cAMP in the target organisms, and - the part that matters conceptually - alpha-MSH peptides enhanced rather than reduced neutrophil killing of both pathogens. The authors' framing was that a molecule combining anti-inflammatory and antimicrobial activity could be useful where infection and inflammation coexist, which is a different and more specific proposition than the general anti-inflammatory positioning KPV is usually sold under. A delivery literature has grown up around the compound and is worth reading as evidence in its own right. Xiao 2017 loaded KPV into hyaluronic-acid-functionalised polymeric nanoparticles of roughly 272 nm, encapsulated those in a chitosan/alginate hydrogel, and gave the whole construct orally to mice with ulcerative colitis; the targeted system outperformed the untargeted one on mucosal healing and TNF-alpha downregulation. Several further groups have built mucoadhesive hydrogels and colon-targeted probes around the same peptide. The existence of that engineering effort is informative: research groups do not build elaborate targeted-delivery vehicles for a molecule that reaches its target easily. It implies that getting KPV where it needs to go is the actual problem, which is a useful corrective to community discussion that treats route as a matter of preference. Every effect described above is from cell culture, mice, or both. There is no reported human outcome for KPV of any kind, positive or negative, and nothing here is a claim that KPV treats, prevents or improves any condition in people.

Research timeline

Dated milestones taken from the primary records: the molecule's discovery, its first registered human study, the trials that shaped the evidence and the regulatory decisions. Each entry links to the record it comes from.

1. Feb 2000A laboratory study reports that alpha-MSH and its last three amino acids, the tripeptide KPV, inhibited Staphylococcus aureus colonies and the yeast Candida albicans in culture, proposing a role in the body's first-line defence. PMID 10670585
2. May 15, 2003In mice with crystal-induced peritonitis, KPV given systemically reduced the influx of white blood cells, and the effect was not blocked by a melanocortin 3/4 receptor antagonist, suggesting KPV works differently from full alpha-MSH. PMID 12750433
3. Oct 17, 2007An Emory University group shows that the gut transporter PepT1 carries KPV into intestinal and immune cells, and that KPV in drinking water reduced two chemically induced forms of colitis in mice. PMID 18061177
4. Jul 5, 2017A mouse study packages KPV in hyaluronic-acid-coated nanoparticles taken by mouth and reports less ulcerative-colitis-like damage in the colon; the delivery work remains animal-only. PMID 28143741
5. Apr 22, 2026FDA's page on compounding safety risks, as updated on this date, lists KPV among substances that had been in Category 2 and whose nominations were withdrawn, stating that FDA identified no human exposure data for KPV by any route. FDA · compounding safety risks, Apr 22, 2026
6. Jul 23, 2026KPV goes before FDA's Pharmacy Compounding Advisory Committee for the pharmacy-compounding (503A) list, evaluated for wound healing and inflammatory conditions; FDA's briefing document concludes that the balance of criteria weighs against listing it. No minutes or vote were posted by 4 Oct 2026. FDA · PCAC briefing document, Jul 23–24, 2026

Records checked Oct 4, 2026

Claims at a glance

The claims most often made about this compound, each with the strongest kind of evidence we found for it. The grade says what was studied, not whether the claim is true; the line beside it says what that study showed.

• Calms gut inflammation and colitisAnimal studies only. Given in drinking water, it reduced chemically induced colitis in two mouse models; no study has tested it in people with bowel inflammation. PMID 18061177
• Reduces inflammation throughout the bodyAnimal studies only. In mice it reduced white-cell build-up in two kinds of induced peritonitis; the same paper found it did not block some inflammatory signals that related peptides did. PMID 12750433
• Works when applied to the skinCell or tissue studies only. On donated human skin it did not pass through intact skin at a detectable level; it crossed only after microneedles or electric current breached the barrier. PMID 28343991
• Treats eczema, psoriasis or acneNo study found. A PubMed search for KPV with eczema, psoriasis, atopic dermatitis, acne or rosacea in the title or abstract returned no records. PubMed search, Oct 7, 2026
• Heals mouth soresAnimal studies only. In rats with chemotherapy-induced mouth sores, a sticky gel carrying KPV improved healing and eating; the gel itself contained another active ingredient. PMID 34846053
• Helps with fat lossAnimal studies only. One 2026 paper: it reduced fat build-up in fat-cell cultures, and mice on a high-fat diet given it by mouth gained less weight. PMID 42585803
• Promotes hair growthNo study found. A PubMed search for KPV or Lys-Pro-Val with hair or alopecia in the title or abstract returned no records. PubMed search, Oct 7, 2026

The reasoning behind each grade, study by study, is in this guide's Benefit & Outcome Review.

Grades checked Oct 7, 2026

Half-life & pharmacokinetics

No published human pharmacokinetic study reports a half-life for KPV. That is a direct statement about the literature, not a hedge: a targeted search returns no study measuring plasma concentration, clearance, Cmax or bioavailability for this peptide in people, and there is no approved product whose label would supply the figure. This matters because specific numbers do circulate. Figures in the range of two to four hours appear on commercial and community pages, sometimes accompanied by a claim that clearance is complete within eight to twelve hours. Those numbers are not traceable to a measurement. If you encounter one, the useful question is which study produced it - and in this case there is no study to name. What can be said honestly is bounded but not nothing. KPV is a tripeptide, and small unmodified peptides of this size are generally cleared quickly, by peptidase degradation and renal filtration, on timescales of minutes to a couple of hours rather than days; nothing about KPV's structure suggests it would be an exception, since it carries no half-life-extending modification of the kind attached to peptides designed for weekly dosing. Separately, the mechanistic literature offers a reason why rapid clearance would not necessarily mean brief activity: the downstream event Dalmasso measured is inhibition of NF-kappaB activation, and transcriptional consequences of that inhibition can outlast the presence of the molecule that caused it. That is a plausible reading of the cell-culture data and it is frequently used to rationalise once- or twice-daily community dosing patterns - but it is an inference from in-vitro work, not established human pharmacodynamics, and it should be labelled as such rather than presented as a duration of action.

Storage & handling

• Lyophilised and unopened: store cold and dark. Long-term storage is typically described at -20 C in a freezer; refrigeration is generally described as adequate for shorter periods. Keep the vial in its carton, as peptides in general are light-sensitive.
• After reconstitution: refrigerate at roughly 2-8 C. The usable window commonly reported in research settings is around two to four weeks; bacteriostatic water's benzyl alcohol is what makes a multi-use window possible at all, since it suppresses microbial growth between withdrawals.
• Do not freeze a reconstituted vial. Freeze-thaw cycling is a recognised degradation route for peptides in solution, and it is the most common avoidable handling error.
• Add bacteriostatic water slowly down the inside wall of the vial rather than directly onto the powder, and swirl rather than shake. Mechanical agitation is a known cause of peptide aggregation.
• Keep the stopper clean and use a fresh needle for each withdrawal. No preservative compensates for repeated entry with a contaminated needle.

Evidence File

The KPV Evidence File: Zero Trials, One Dimer, Two Buried Negatives

KPV is one of the rare research-market peptides whose mechanistic literature is genuinely strong and whose clinical literature is genuinely empty, and the gap between those two facts is where most commercial copy goes wrong. This file works through the registry and database record term by term, naming every search string used so that any reader can reproduce the result rather than take it on trust. It also handles a problem specific to this compound: in the biomedical literature the letters KPV denote at least four unrelated things, so any publication count that has not been de-homonymised is wrong before it is quoted.

• 10 registry search terms run, 0 KPV studies returned
• 3 circulating figures traced to origin
• 2 negative results recovered from the primary literature
• 1 KPV-derived molecule reported in human investigation, 0 published results

Sourcing File

The KPV Sourcing File: Why a Clean Mass Spectrum Proves Almost Nothing Here

Most peptide sourcing advice generalises, and for KPV the generalisations fail in a specific and instructive way. This is a three-residue molecule with two basic nitrogens, one proline in the middle, and a composition that several other tripeptides share exactly. Each of those structural facts changes what a certificate of analysis can and cannot establish, and two of them are unusual enough that standard COA guidance does not cover them. This file works through the verified identity block, the salt-form arithmetic that governs how much peptide a labelled vial actually contains, the named degradation product, and what a certificate would need to show to settle identity rather than merely purity.

• 6 sequence isomers share one exact mass
• 5 salt-form scenarios costed against a 5 mg label
• up to 40% of labelled vial mass can be counter-ion
• 0 FDA UNII exists for this compound

Benefit & Outcome Review

The KPV Benefit Review: Eighteen Marketed Claims, Graded by Species

Benefit reviews usually grade claims as strong, moderate or weak. For KPV that scale is the wrong instrument, because the variable separating the claims is what was in the dish or the cage. Some KPV claims rest on four disease models run by two independent laboratories; some rest on a single paper from the year 2000; some rest on experiments in which the tested molecule was a conjugate, a dimer or a capped analogue rather than KPV; and several rest on nothing in the literature at all. This review states the species first for every claim and names the search behind every absence.

• 18 marketed claims graded by species
• 0 human outcome data behind any of them
• 3 claims with no primary study in PubMed
• 1 claim contradicted by a direct human-tissue measurement

Guide FAQ

Quick answers about guide scope, access, and educational use context.